Aeration is a process by which air is circulated through, mixed with or dissolved in a liquid or substance. Various aeration techniques have been used to oxidize, reduce, evaporate or change certain compounds found in liquids. For example, tannins are the chemicals that make wine astringent. In older wines, tannins break down in the bottle as the wine ages, but in younger wines tannins can mask some of a wine's more delicate and sought after flavors. Aerating a younger wine for a period of time causes the tannins to break down and lessens the astringency. Although most wines improve with as little as 15-20 minutes of aeration time, young wines typically have high tannin levels and may need more time to aerate before enjoying. For example, a young cabernet sauvignon may need about an hour of aeration for flavor softening. Aeration can also be used to evaporate other volatile and undesirable compounds in a beverage while retaining desirable ones. In particular, there are a number of compounds that are reduced with aeration, such as sulfites, which are added to certain beverages to prevent oxidation and microbial activity but produce unpleasant smells.
Typical approaches to reduce aeration time include use of fountains, cascades, paddle-wheels or cones. However, these aeration devices are often inconvenient to use, require additional expense and clean-up time, and cannot be fine tuned to provide a desired level of aeration. For example, dispensing a boxed wine with a typical aerator requires one hand to hold a glass, another hand to press the dispensing button on a spigot, and a third hand to hold an aerator located between the glass and the spigot, which is inconvenient for practical use. As a result, beverage distributors and manufactures continue to seek systems that enable convenient beverage aeration, control over the amount of air a beverage is combined with and reduce the aeration time.